Answer to Question #160470 in General Chemistry for Emilee C Plasse

Question

1. Using the isotope data in the table below, calculate the average atomic mass of potassium.

Isotope

Percent Abundance

Isotope Mass (amu)

Potassium-39

93.258

38.964

Potassium-40

0.01

39.964

Potassium-41

6.730

40.961

Answer 1

Average Atomic mass= M₁X₁+M₂X₂+M₃X₃

Where, M₁ , M₂ & M₃ are atomic masses of isotopes and X₁ ,X₂ & X₃ are percentage abundance

Average Atomic mass = 38.964×0.93258+0.0001×39.964 + 0.06730×40.961

= 39.098 amu

Average Atomic mass = [39.098] amu